When the PC edition of Resident Evil 6 releases later this year, players will be able to download characters from Left 4 Dead 2 to use in the game. Meanwhile, Left 4 Dead 2 players will get some new content as well in the form of Resident Evil 6 enemies transported into the game’s campaigns. Content for both games will be totally free when it’s available.

People love Left 4 Dead. Given the popularity of zombies, from books like Max Brooks’ perennial bestseller World War Z to TV hits like AMC’s The Walking Dead, it’s not terribly surprising that Valve’s multiplayer zombie shooters have been hits over the past four and a half years. What started as an entertaining experiment for Valve back in 2008 has gone on to sell more than 12 million copies through a sequel and multiple downloadable expansions. Even just a little bit of new content is enough to excite the franchise’s community.

Capcom may be getting the sweeter end of the deal in this case, though. As much as people love Left 4 Dead, they certainly don’t care for Resident Evil 6. The game received a critical drubbing when it released in October 2012—Digital Trends found it to be a mediocre game but still enough of an astoundingly gaudy spectacle to merit some interest—but it’s real failure was with players, as the game sold millions of copies fewer than Capcom expected. After months of bad press, it’s doubtful that some Left 4 Dead 2-related fan service will help Resident Evil 6 find new life on PC.

The future for both series, meanwhile, is looking up. While no plans are set in stone just yet, Valve’s Chet Faliszek said in October that a Left 4 Dead 3 is very likely to come out “some time down the road.” Capcom meanwhile, has decided that it will stop chasing the lucrative online action game crowd with future Resident Evil games. Producer Masachika Kawata said in February that the next Resident Evil will emphasize “horror and fear” in an attempt to make the series unique again.